1. Field of the Invention
The invention relates to a hydrostatic drive system comprising a required-flow regulated pump and a plurality of consumers which are connected thereto and which can each be actuated by means of a directional control valve, which performs a throttling function in intermediate positions. The consumers can be connected downstream of the directional control valves via non-return valves to a LS-line which leads to a required-flow regulator actively connected to the pump. To provide for load-independent allocation of the delivered flow when consumers are simultaneously actuated, each directional control valve is assigned a pressure compensator which can be controlled directly or indirectly by a signal difference formed from a load pressure signal and a delivered pressure signal. The load pressure signal is derived from the highest of the load pressures occurring downstream of the directional control valves and is conveyed in the LS-line. The delivered pressure signal is derived from the pressure upstream of the directional control valves.
2. Description of the Prior Art
In such drive systems, the degree of opening of the directional control valves, independently of the load pressure of the consumers, determines the volume flow of pressure medium which is supplied to the consumers, and thus the speed of movement (linear or rotational) of the consumers. The ratio of the movement speeds of the individual consumers one to another is continuously maintained by virtue of the action of the pressure compensators, even when the pump delivery capacity is exhausted, in which case the speeds of the consumers are reduced by a proportional reduction in the supply of pressure medium.